Method of rapid generation-adding breeding of rice

ABSTRACT

The invention discloses a method of rapid generation-adding breeding of rice in the technical field of rice breeding, including soaking seeds of the rice, germination, seedlings cultivation, managing and regulating of the rice at the growth stage, and harvesting the rice. The managing and regulating the rice at the growth stage includes dynamic light quality and photoperiod control in vegetative growth period, heading period and pustulation period; growth period involves light environment regulation with the ratio of red light:blue light:white light of 0.8-1:0.8-1:1.0, photoperiod of 16-18 h; heading period involves light environment regulation with the ratio of red light:blue light:white light of 1-2:0.5-1:1, photoperiod of 12-13.5 h; and pustulation period includes light environment regulation with the ratio of red light:blue light:white light of 1-2:1:1, photoperiod of 16-18 h.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 17/582,177, filed onJan. 24, 2022, which claims priority to Chinese Patent Application No.202111305500.2, filed on Nov. 5, 2021, the contents of which are herebyincorporated by reference.

TECHNICAL FIELD

The invention relates to the technical field of rice breeding, and inparticular to a method of rapid generation-adding breeding of rice.

BACKGROUND

Rice is the third largest food crop in the world. The cultivation ofhigh-quality seeds of the rice is the key to ensure the yield andquality of rice. At present, there are two common methods of ricebreeding. One is conventional cross self-breeding, the crop obtainsstable traits after repeated cross-selfing, and high-quality ricevarieties are cultivated. The other is transgenic breeding, whichrealizes the improvement at the gene level by means of transgene andthen stabilizes the rice varieties with excellent traits. Due to thelimitation of regional climatic conditions, conventional rice breedingcan only add 2-3 generations a year, and it often takes several years oreven ten years to cultivate a high-quality rice variety. Transgenicbreeding, has the advantage of a relatively short breeding cycle, andthe target variety is usually obtained after 1-2 times of cultivation.However, considering the food security problem, the conventionalbreeding method with a long cycle is generally adopted for rice as afood crop, which is difficult to meet the market demand for high-qualityseed sources in rice planting. Therefore, there is an urgent need for afast and safe breeding method to resolve the current problems of ricebreeding.

SUMMARY

The purpose of the invention is to provide a method of rapidgeneration-adding breeding of rice to solve the above-mentioned problemsexisting in the prior art, which provides technical support forrealizing rapid cultivation of high-quality rice varieties in limitedland area, shortening the conventional breeding cycle and ensuring foodsecurity by accurately regulating the dynamic light quality andphotoperiod environment in rice growth periods.

To achieve the above objective, the invention provides the followingscheme:

the invention provides a method of rapid generation-adding breeding ofrice, which includes soaking seeds of the rice, germination, seedlingscultivation, managing and regulating of the rice at the growth stage andharvesting the rice, wherein the managing and regulating of the rice atthe growth stage includes regulation of dynamic light quality andphotoperiod environment during vegetative growth period, heading periodand pustulation period of the rice; wherein

the regulation during the vegetative growth period includes: cultivatingunder the Deep Flow Technology condition of the mixed light emittingdiode (LED) light source with the ratio of red light:blue light:whitelight of 0.8-1:0.8-1:1.0, the photoperiod of 16-18 h and additionalHoagland nutrient solution with 5%-10% of calcium nitrate;

the regulation during the heading period includes: cultivating under thesoilless cultivation technology condition of the mixed LED light sourcewith the ratio of red light:blue light:white light of 1-2:0.5-1:1,photoperiod of 12-13.5 h and additional Hoagland nutrient solution with5%-15% of dipotassium hydrogen phosphate (Deep-Flow Technology, DFT;Aeroponics); and

the regulation during the pustulation period includes: cultivating underthe soilless cultivation technology condition of the mixed light sourcewith the ratio of red light:blue light:white light of 1-2:1:1,photoperiod of 16-18 h and additional Hoagland nutrient solution with5%-10% of dipotassium hydrogen phosphate (Deep-Flow Technology, DFT;Aeroponics); wherein

the wavelength of red light is 660 nm, the wavelength of blue light is450 nm, and the wavelength of white light is 400-700 nm.

Preferably, the illumination intensity at vegetative growth period,heading stage and pustulation period is set to 200-300 μmol m⁻²s⁻¹,350-450 μmol m⁻²s and 500-700 μmol m⁻²s⁻¹, respectively.

Preferably, soaking seeds of the rice includes: selecting pest-freeseeds of the rice with full grains, cleaning and soaking seeds for 12-24h.

Preferably, germination means culturing the seeds of the rice aftersoaking at 22-25° C. in dark for 36-48 h.

Preferably, seedling growing means culturing germinated seeds of therice in a mixed light source with red light:blue light of 2-5:1,illumination intensity of 100-150 μmolm⁻²s⁻¹, and photoperiod of 14-18h.

Preferably, during the vegetative growth period, the seedlings aretransplanted and grown under the soilless cultivation technologycondition of the mixed light source with the ratio of red light:bluelight:white light of 0.8-1:0.8-1:1.0, the photoperiod of 16-18 h,illumination intensity of 200-300 μmolm⁻²s⁻¹ and the addition ofHoagland nutrient solution with 5%-10% of calcium nitrate (Deep-FlowTechnology, DFT; Aeroponics);

Preferably, before harvesting, the day/night temperature of ricebreeding is (27-30° C.)/(23-25° C.), and the air relative humidity isset at 65-85%.

Preferably, harvesting means mature rice ears are harvested, threshed,and treated for 5-7 days under air temperature 28-30° C., air humidityless than 40% and good ventilation, and the water content of seeds isreduced to 6%-13% and then the seeds are stored at low temperatures.

Preferably, the low temperature is 0-4° C.

The invention discloses the following technical effects:

Based on the features of rice growth period, the invention accuratelyregulates and controls the dynamic light quality, photoperiod, day/nighttemperature, relative air humidity, nutrition supply and otherenvironmental factors, and provides a method of rapid generation-addingbreeding of rice. The method scientifically and reasonably shortens thegrowth period of rice, realizes quick harvest about 60 days afterplanting, shortens the growth period of conventional rice about 120 daysby half, and is expected to achieve 5-6 crops a year. Under themanagement conditions of specific light environment, day/nighttemperature, relative air humidity, nutrition supply and otherenvironmental factors in the plant factory, the rice can grow faster,blossom early and grow seeds quickly. Specifically, rice seedlingcultivation should be taken around 7 days after sowing and it takesabout 38-47 days from transplanting to heading, while harvesting isaround 53-65 days after sowing. The yield per unit area of a singlelayer is 0.81-1.2 kg (average 0.98 kg), which is equivalent to540.3-800.4 kg (average 653 kg) per mu (1 mu=666.67 m²). Therefore, theinvention provides a brand-new and effective method of rapidgeneration-adding breeding under the controllable environmentalconditions of plant factory, provides technical support for realizingrapid cultivation of high-quality rice varieties in limited land area,shortening the conventional breeding cycle and ensuring food security,and can meet a large number of market demands for high-quality rice seedsources.

BRIEF DESCRIPTION OF THE FIGURES

In order to more clearly explain the embodiments of the invention or thetechnical solutions in the prior art, the drawings needed in theembodiments will be briefly introduced below. Obviously, the drawings inthe following description are only some embodiments of the invention,and for ordinary technicians in the field, other drawings can beobtained according to these drawings without creative efforts.

FIGS. 1A and 1B are images of heading and fruiting of rice in Embodiment1, respectively.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Various exemplary embodiments of the invention will be described indetail below. This detailed description should not be considered as alimitation of the invention, but should be understood as a more detaileddescription of some aspects, features and embodiments of the invention.

It should be understood that the terms used in this invention are onlyfor describing specific embodiments, and are not used to limit theinvention. In addition, for the numerical range in the invention, itshould be understood that each intermediate value between the upperlimit and the lower limit of the range is also specifically disclosed.Any stated value or intermediate value within the stated range and anyother stated value or every smaller range between intermediate valueswithin the stated range are also included in the invention. The upperand lower limits of these smaller ranges can be independently includedor excluded from the range.

Unless otherwise specified, all technical and scientific terms usedherein have the same meaning as commonly understood by the ordinarytechnicians in the field of this invention. Although the invention onlydescribes the preferred methods and materials, any methods and materialssimilar or equivalent to those described herein can also be used in thepractice or testing of the invention. All documents mentioned in thisspecification are incorporated by reference to disclose and describe themethods and/or materials related to the documents. In case of conflictwith any incorporated documents, this specification shall prevail.

Without departing from the scope or spirit of the invention, it isobvious to those skilled in the art that many modifications and changesmay be made to the specific embodiments of the invention. Otherembodiments obtained from the description of the invention will beobvious to the skilled person. The specification and Embodiments of thisapplication are exemplary only.

The words “including”, “comprising”, “having” and “containing” used inthis invention are all open terms, that is, they mean including but notlimited to.

In some embodiments, the method of rapid generation-adding breeding ofrice can at least include soaking seeds of the rice, germination,seedling cultivation, managing and regulating of the rice at the growthstage and harvesting. The managing and regulating of the rice at thegrowth stage includes the regulation of dynamic light quality andphotoperiod environment in vegetative growth period, heading period andpustulation period. For example, in the growth management period,according to the mixed light source with the ratio of red light (660nm):blue light (450 nm):white light (400 nm) of 1:1:1, the photoperiodis 16 h, the illumination intensity is 450 μmolm⁻²s⁻¹, the day and nighttemperatures are 30° C. and 25° C. respectively, the air humidity is85%, and Hoagland nutrient solution with 15% potassium hydrogenphosphate (K₂HPO₄) is used for soilless cultivation. Heading 45 daysafter sowing, harvesting 63 days after sowing, the single-layer yieldper unit area is 566.7 kg/mu, the plant height is 77.5 cm, the number oftillers is 28.8, the number of grains is 118.3, the fresh weightoverground is 40.5 g, the dry weight overground is 12.6 g, theunderground fresh weight is 33.7 g, the underground dry weight is 7 g,the maturing rate is 71.3%, and the grain-straw ratio is 0.67.

In some embodiments, soaking seeds of the rice means selecting seeds ofthe rice with full grains, cleaning and soaking them for 12-14 h.

In some embodiments, sprouting means culturing seeds of the rice aftersoaking at 22-25° C. in dark for 36-48 h.

In some embodiments, seedling growing means culturing the germinatedseeds of the rice in a mixed light source with red light:blue light of2-5:1, illumination intensity of 100-150 μmolm⁻²s⁻¹, and photoperiod of14-18 h.

In some embodiments, the regulation during the vegetative growth periodincludes adding Hoagland nutrient solution with 5%-10% of calciumnitrate to carry out soilless culture under the conditions of mixedlight source with the ratio of red light:blue light:white light of0.8-1:0.8-1:1.0, photoperiod of 16-18 h and illumination intensity of200-300 μmolm⁻²s⁻¹.

In some embodiments, regulation during the heading period means addingHoagland nutrient solution with 5%-15% of dipotassium hydrogen phosphateto carry out soilless culture under the conditions of mixed light sourcewith the ratio of red light:blue light:white light of 1-2:0.5-1:1,photoperiod of 12-13.5 h and illumination intensity of 350-450μmolm⁻²s⁻¹.

In some embodiments, the regulation during the pustulation periodincludes adding Hoagland nutrient solution with 5%-15% of dipotassiumhydrogen phosphate to carry out soilless culture under the conditions ofmixed LED light source with the ratio of red light:blue light:whitelight of 1-2:1:1, photoperiod of 16-18 h and illumination intensity of500-700 μmolm⁻²s⁻¹.

In some embodiments, the wavelength of red light is 660 nm, thewavelength of blue light is 450 nm, and the wavelength of white light is400-700 nm.

In some embodiments, the daytime/night time temperature of rice breedingis (27-30° C.)/(23-25° C.) and the relative humidity of air is 65-85%during the above-mentioned period of raising seedlings and growthmanagement and regulation.

In some embodiments, the harvesting process includes harvesting andthreshing mature rice ears, treating them for 5-7 days at airtemperature of 28-30° C., air humidity of less than 40% and goodventilation, reducing the moisture content of seeds to 6%-13%, andstoring the seeds at low temperature of 0-4° C.

The following is a further description of the regulation of eachbreeding stage with specific Embodiments.

Embodiment 1

A method of rapid generation-adding breeding of rice includes thefollowing steps:

(1) soaking seeds: the seeds of the rice with full grains are selectedand washed with tap water for 2-3 times, and then soaked in deionizedwater for 12 h.

(2) germination: the soaked seeds are evenly spread in a germinationtray covered with wet gauze (10×10×5 cm), 10 mL deionized water isadded, and the seeds are cultured at 22° C. for 36 h in the dark.

(3) seedling cultivation: the germinated seeds are sowed into a holetray with grass carbon as the seedling substrate, and grown in a plantfactory under a mixed LED light source with red light (600 nm):bluelight (450 nm) of 2:1, with an illumination intensity of 100 μmolm⁻²s⁻¹,the photoperiod of 14 h, the day/night temperature of 27° C./23° C. andthe air humidity of 65%.

(4) regulation during vegetative growth period: cultivation is carriedout under the conditions of mixed light source with the ratio of redlight:blue light:white light of 0.8:0.8:1.0, the photoperiod of 16 h,the illumination intensity of 200 μmolm⁻²s⁻¹, the day and nighttemperature of 27° C./23° C., the air humidity of 65% and soillessculture technology (Deep Flow Technology, DFT; Aeroponics) of addingHoagland nutrient solution with 5% of calcium nitrate (Ca(NO₃)₂).

(5) regulation during heading period: cultivation is carried out underthe conditions of mixed light source with the ratio of red light:bluelight:white light of 1:0.5:1, photoperiod of 12 h, illuminationintensity of 350 μmolm⁻²s⁻¹, day and night temperature of 30° C./23° C.,air humidity of 70% and soilless culture technology (Deep FlowTechnology, DFT; Aeroponics) of adding Hoagland nutrient solution with5% of dipotassium hydrogen phosphate (K₂HPO₄).

(6) regulation during the pustulation period: cultivation is carried outunder the conditions of the LED light source with the mixture of redlight (660 nm):blue light (450 nm):white light (400 nm) of 1:1:1, thephotoperiod of 16 h, the illumination intensity of 500 molm⁻²s⁻¹, theday and night temperature of 30° C./23° C., the air humidity of 70% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 5% of dipotassium hydrogenphosphate (K₂HPO₄).

(7) harvesting: the ripe rice ears are harvested and separated, thenspread on the non-woven fabric, treated for 5 days at air temperature of30° C., air humidity of <40% and ventilation; after the water content ofseeds is decreased to 6%, the seeds are put into a 100-mesh gauze bag tobe stored at a low temperature of 4° C. under dry conditions.

In the above scheme, seedling cultivation in plant factory is carriedout 7 days after sowing and heading is carried out 42 days afterseedling being planting, while it takes 57 days from rice sowing toharvesting. The yield per unit area of single layer is 0.85 kg, which isequivalent to 566.7 kg per mu (8500.5 kg per hectare).

Embodiment 2

A method of rapid generation-adding breeding of rice includes thefollowing steps:

(1) soaking seeds: the seeds of the rice with full grains are selectedand washed with tap water for 2-3 times, and then soaked in deionizedwater for 20 h.

(2) seedling cultivation: the soaked seeds are evenly spread in agermination tray covered with wet gauze (10×10×5 cm), 10 mL deionizedwater is added, and the seeds are cultured at 25° C. for 36 h in thedark.

(3) raising seedlings: the germinated seeds are sowed into a hole traywith grass carbon as the seedling substrate, and cultured in a plantfactory under a mixed LED (light-emitting diode) light source with redlight (600 nm):blue light (450 nm) of 2:1, with an illuminationintensity of 100 μmolm⁻²s⁻¹, the photoperiod of 14 h, the day/nighttemperature of 27° C./23° C. and the air humidity of 70%.

(4) regulation during vegetative growth period: cultivation is carriedout under the conditions of mixed light source with the ratio of redlight:blue light:white light of 0.8:0.8:1.0, the photoperiod of 16 h,the illumination intensity of 200 μmolm⁻²s⁻¹, the day and nighttemperature of 27° C./23° C., the air humidity of 65% and soillessculture technology (Deep Flow Technology, DFT; Aeroponics) of addingHoagland nutrient solution with 5% of calcium nitrate (Ca(NO₃)₂).

(5) regulation during heading period: cultivation is carried out underthe conditions of mixed light source with the ratio of red light:bluelight:white light of 1:0.5:1, photoperiod of 12 h, illuminationintensity of 350 μmolm⁻²s⁻¹, day and night temperature of 30° C./23° C.,air humidity of 70% and soilless culture technology (Deep FlowTechnology, DFT; Aeroponics) of adding Hoagland nutrient solution with5% of dipotassium hydrogen phosphate (K₂HPO₄).

(6) regulation during the pustulation period: cultivation is carried outunder the conditions of the LED light source with the mixture of redlight (660 nm):blue light (450 nm):white light (400 nm) of 1:1:1, thephotoperiod of 16 h, the illumination intensity of 500 molm⁻²s⁻¹, theday and night temperature of 30° C./23° C., the air humidity of 70% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 5% of dipotassium hydrogenphosphate (K₂HPO₄).

After the mature rice ears are harvested and threshed, the seeds aretreated for 5-7 days under the condition of air temperature, airhumidity <40% and good ventilation, and the moisture content of seeds isreduced to 6%-13% and then stored at low temperature.

(7) harvesting: the ripe rice ears are harvested and separated, thenspread on the non-woven fabric, treated for 5 days at air temperature of30° C., air humidity of <40% and ventilation; after the water content ofseeds is reduced to 6%, the seeds are put into a 100-mesh gauze bag tobe stored at a low temperature of 4° C. under drying conditions.

In the above scheme, seedling cultivation is carried out 7 days aftersowing, and the heading time is carried out 38 days after seedling beingtransplanted, while it takes 53 days from sowing to harvesting. Theyield per unit area of single layer is 1.2 kg, which is equivalent to702.4 kg per mu (10530 kg per hectare).

Embodiment 3

A method of rapid generation-adding breeding of rice includes thefollowing steps:

(1) soaking seeds: the seeds of the rice with full grains are selectedand washed with tap water for 2-3 times, and then soaked in deionizedwater for 22 h.

(2) germination: the soaked seeds are evenly spread in a germinationtray covered with wet gauze (10×10×5 cm), 12 mL deionized water isadded, and the seeds are cultured at 22° C. for 48 h in the dark.

(3) seedling cultivation: the germinated seeds are sowed into a holetray with grass carbon as the seedling substrate, and grown in a plantfactory under a mixed LED (light-emitting diode) light source with redlight (600 nm):blue light (450 nm) of 3:1, with an illuminationintensity of 125 μmolm⁻²s⁻¹ the photoperiod of 18 h, the day/nighttemperature of 27° C./25° C. and the air humidity of 70%.

(4) regulation during vegetative growth period: cultivation is carriedout under the conditions of mixed LED light source with the ratio of redlight (660 nm):blue light (450 nm): white light (500 nm) of 1:1:1, thephotoperiod of 16 h, the illumination intensity of 250 μmolm⁻²s⁻¹, theday and night temperature of 27° C./25° C., the air humidity of 70% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 5% of calcium nitrate (Ca(NO₃)₂).

(5) regulation during heading period: cultivation is carried out underthe conditions of mixed light source with the ratio of red light (660nm):blue light (450 nm):white light (500 nm) of 1:1:1, photoperiod of13.5 h, illumination intensity of 400 μmolm⁻²s⁻¹, day and nighttemperature of 27° C./25° C., air humidity of 70% and soilless culturetechnology (Deep Flow Technology, DFT; Aeroponics) of adding Hoaglandnutrient solution with 5% of dipotassium hydrogen phosphate (K₂HPO₄).

(6) regulation during the pustulation period: cultivation is carried outunder the conditions of the LED light source with the mixture of redlight (660 nm):blue light (450 nm):white light (500 nm) of 1:1:1, thephotoperiod of 16 h, the illumination intensity of 550 μmolm⁻²s⁻¹, theday and night temperature of 27° C./25° C., the air humidity of 70% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 5% of dipotassium hydrogenphosphate (K₂HPO₄).

After the mature rice ears are harvested and threshed, the seeds aretreated for 5-7 days under the condition of air temperature, airhumidity <40% and ventilation, and the moisture content of seeds isreduced to 6%-13% and then stored at low temperature.

(7) harvesting: the ripe rice ears are harvested and separated, thenspread on the non-woven fabric, treated for 6 days at air temperature of29° C., air humidity of <40% and ventilation; after the water content ofseeds is reduced to 10%, the seeds are put into a 100 mesh gauze bag tobe stored at a low temperature of 2° C. under drying conditions.

In the above scheme, seedling cultivation is carried out 7 days aftersowing and the heading time is carried out 45 days after seedling beingtransplanted, while it takes 60 days from rice seeds sowing toharvesting. The yield per unit area of single layer is 0.98 kg, which isequivalent to 653 kg per mu (9795 kg per hectare).

Embodiment 4

A method of rapid generation-adding breeding of rice includes thefollowing steps:

(1) soaking seeds: the seeds of the rice with full grains are selectedand washed with tap water for 2-3 times, and then soaked in deionizedwater for 24 h.

(2) seedling cultivation: the soaked seeds are evenly spread in agermination tray covered with wet gauze (10×10×5 cm), 15 mL deionizedwater is added, and the seeds are cultured at 25° C. for 36 h in thedark.

(3) seedling cultivation: the germinated seeds are sowed into a holetray with grass carbon as the seedling substrate, and cultured in aplant factory under a mixed LED (light-emitting diode) light source withred light (600 nm):blue light (450 nm) of 5:1, with an illuminationintensity of 100 μmolm⁻²s⁻¹, the photoperiod of 18 h, the day/nighttemperature of 27° C./25° C. and the air humidity of 70%.

(4) regulation during vegetative growth period: cultivation is carriedout under the conditions of mixed LED light source with the ratio of redlight (660 nm):blue light (450 nm):white light (700 nm) of 0.8:0.8:1,the photoperiod of 16 h, the illumination intensity of 250 molm−2s−1,the day and night temperature of 27° C./25° C., the air humidity of 70%and soilless culture technology (Deep Flow Technology, DFT; Aeroponics)of adding Hoagland nutrient solution with 5% of calcium nitrate(Ca(NO₃)₂).

(5) regulation during heading period: cultivation is carried out underthe conditions of mixed light source with the ratio of red light (660nm):blue light (450 nm):white light (700 nm) of 0.5:1:1, photoperiod of12 h, illumination intensity of 350 μmolm⁻²s⁻¹, day and nighttemperature of 27° C./25° C., air humidity of 70% and soilless culturetechnology (Deep Flow Technology, DFT; Aeroponics) of adding Hoaglandnutrient solution with 5% of dipotassium hydrogen phosphate (K₂HPO₄).

(6) regulation during the pustulation period: cultivation is carried outunder the conditions of the LED light source with the mixture of redlight (660 nm):blue light (450 nm):white light (700 nm) of 1:1:1, thephotoperiod of 16 h, the illumination intensity of 500 μmolm⁻²s⁻¹, theday and night temperature of 27° C./25° C., the air humidity of 70% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 5% of dipotassium hydrogenphosphate (K₂HPO₄).

(7) harvesting: the ripe rice ears are harvested and separated, thenspread on the non-woven fabric, treated for 5 days at air temperature of30° C., air humidity of <40% and ventilation; after the water content ofseeds is reduced to 13%, the seeds are put into a 100 mesh gauze bag tobe stored at a low temperature of 4° C. under drying conditions.

In the above scheme, seedling cultivation is carried out 7 days aftersowing and the heading time is carried out 42 days after seedling beingtransplanted, while it takes 58 days from rice seed sowing toharvesting. The yield per unit area of single layer is 0.81 kg, which isequivalent to 540.3 kg per mu (8104.5 kg per hectare).

Embodiment 5

A method of rapid generation-adding breeding of rice includes thefollowing steps:

(1) soaking seeds: the seeds of the rice with full grains are selectedand washed with tap water for 2-3 times, and then soaked in deionizedwater for 24 h.

(2) germination: the soaked seeds are evenly spread in a germinationtray covered with wet gauze (10×10×5 cm), 15 mL deionized water isadded, and the seeds are cultured at 25° C. for 48 h in the dark.

(3) seedling cultivation: the germinated seeds are sowed into a holetray with grass carbon as the seedling substrate, and cultured in aplant factory under a mixed LED (light-emitting diode) light source withred light (600 nm):blue light (450 nm) of 5:1, with an illuminationintensity of 150 μmolm⁻²s⁻¹, the photoperiod of 18 h, the day/nighttemperature of 30° C./25° C. and the air humidity of 85%.

(4) regulation during vegetative growth period: cultivation is carriedout under the conditions of mixed LED light source with the ratio of redlight (660 nm):blue light (450 nm):white light (700 nm) of 1:1:1, thephotoperiod of 18 h, the illumination intensity of 300 μmolm⁻²s⁻¹, theday and night temperature of 30° C./25° C., the air humidity of 85% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 10% of calcium nitrate(Ca(NO₃)₂).

(5) regulation during heading period: cultivation is carried out underthe conditions of mixed light source with the ratio of red light (660nm):blue light (450 nm):white light (700 nm) of 2:1:1, photoperiod of13.5 h, illumination intensity of 450 μmolm⁻²s⁻¹, day and nighttemperature of 30° C./25° C., air humidity of 85% and soilless culturetechnology (Deep Flow Technology, DFT; Aeroponics) of adding Hoaglandnutrient solution with 15% of dipotassium hydrogen phosphate (K₂HPO₄).

(6) regulation during the pustulation period: cultivation is carried outunder the conditions of the LED light source with the mixture of redlight (660 nm):blue light (450 nm):white light (700 nm) of 2:1:1, thephotoperiod of 18 h, the illumination intensity of 500 μmolm⁻²s⁻¹, theday and night temperature of 30° C./25° C., the air humidity of 85% andsoilless culture technology (Deep Flow Technology, DFT; Aeroponics) ofadding Hoagland nutrient solution with 10% of dipotassium hydrogenphosphate (K₂HPO₄).

(7) harvesting: the ripe rice ears are harvested and separated, thenspread on the non-woven fabric, treated for 7 days at air temperature of30° C., air humidity of <40% and ventilation; after the water content ofseeds is reduced to 13%, the seeds are put into a 100 mesh gauze bag tobe stored at a low temperature of 4° C. under drying conditions.

In the above scheme, seedling cultivation is carried out 7 days aftersowing and the heading time is carried out 41 days after seedling beingtransplanted, while it takes 56 days from rice seed sowing toharvesting. The yield per unit area of single layer is 1.08 kg, which isequivalent to 720.04 kg per mu (10800.6 kg per hectare).

In some embodiments, the managing and regulating of the rice at thegrowth stage can be performed based on a rice breeding managementplatform, which includes a processor.

In some embodiments, the managing and regulating of the rice at thegrowth stage may further include that the processor determines one ormore target illumination parameters of the target growth period based onthe historical growth parameters of the historical growth period and thepreset illumination parameters in combination with a machine learningmodel, and the above process may include the following steps.

S1, the processor acquires historical growth parameters of at least onehistorical growth period of the seeds of the rice before a target growthperiod, wherein the target growth period and the at least one historicalgrowth period is at least one of vegetative growth period, heading stageand pustulation period.

The historical growth period may be the growth stage that rice hasexperienced. The target growth period may be the growth stage that riceis about to enter. For example, if rice is about to enter the headingstage, the vegetative growth period is the historical growth period ofthe rice, and the target growth period can be either heading stage orpustulation period.

Historical growth parameters refer to the parameters of the growthenvironment of rice during the historical growth period. In someembodiments, historical growth parameters include historicalillumination parameters, historical nutrient solution and itsconcentration, historical temperature, historical humidity, historicalprocessing time, historical proportion of red, blue and white light,etc.

Historical lighting parameters refer to the parameters related to lightenvironment during the historical growth period of rice. In someembodiments, historical lighting parameters may include historicallighting intensity and historical lighting time.

S2, the processor acquires one or more preset illumination parameters.

The preset illumination parameters refer to one or more presetillumination parameters based on the actual needs of different breedingstages, which can include preset illumination time, preset illuminationintensity, etc.

In some embodiments, the preset illumination parameters can be obtainedthrough the input of relevant staff or based on historical breedingdata. In some embodiments, the preset lighting parameters can also beobtained in other possible ways.

S3, for each of the one or more preset illumination parameters, theprocessor determines the predicted growth quality of the seeds of therice during the target period under the action of the presetillumination parameters based on the illumination prediction modelaccording to the historical growth parameters of the at least onehistorical growth period and the preset illumination parameters.

The predicted growth quality refers to at least one quality graderelated to the growth of rice during the target growth period under thecultivation condition with one or more preset illumination parameters.The preset growth quality can be determined according to leaf areas, asize and a count of rice heads, tiller number, plant height, etc.

In some embodiments, the processor can combine the illuminationprediction model to determine the target growth parameters during thetarget growth period. In some embodiments, the input of the illuminationprediction model may include historical growth parameters of at leastone historical growth period, for example, preset illuminationparameters of the target growth period, at least one historicalillumination time and at least one historical illumination intensitycorresponding to at least one historical growth period.

In some embodiments, the input of the illumination prediction model mayalso include the growth morphology images at multiple time points ineach of at least one historical growth period, and the nutrientdetection results of the nutrient solution at multiple time points ineach of at least one historical growth period. Among them, the nutrientdetection results of the nutrient solution include the contents of traceelements that are important for rice growth in the nutrient solution,such as nitrogen, phosphorus, potassium and so on. In some embodiments,the nutrient detection results of the nutrient solution can be obtainedby manual input or by a nutrient solution nutrient detector.

In some embodiments, the output of the illumination prediction model mayinclude the growth quality of rice during the target growth period.Among them, the growth quality of rice can be expressed by thecomprehensive score of growth quality. For example, the comprehensivescore is determined according to the indexes such as leaf size, a sizeand a count of rice heads, tiller number, plant height and weights. Theweight of each index can be set manually according to the differentcultivation objectives in each growth stage. For example, if thecultivation objective in the vegetative stage is the leaf development ofrice seedlings, the leaf areas and the dry weight of the whole seedlingsin the vegetative stage will have higher values in determining thegrowth quality in this stage. For another example, if the cultivationobjective during the pustulation period is the growth of rice fruits,the seed numbers and weight per a thousand seeds during the pustulationperiod will have higher values in determining the growth quality in thisstage.

In some embodiments, the type of illumination prediction model may beDNN, CNN, etc.

In some embodiments, the illumination prediction model may includemultiple layers. The illumination prediction model can at least includean image feature layer and growth feature layer. The output of the imagefeature layer may be used as the input of the growth feature layer, andthe output of the growth feature layer is the output of the illuminationprediction model.

In some embodiments, the image feature layer may be CNN model, thegrowth feature layer may be RNN model, and they may also be other modelsthat can realize the same processing.

In some embodiments, the image feature layer may process the images ofrice and extract image features. The image feature layer may process theinput growth morphology image of a certain historical growth period andextract the image features of the growth phenotype.

In some embodiments, the input of the growth feature layer may includehistorical growth parameters of at least one historical growth period.The historical growth parameters of at least one historical growthperiod can be expressed by a control parameter matrix m*n. Each row inthe matrix is a historical growth parameter feature of a historicalgrowth period, m is the number of historical growth periods, and m canbe the preset value of 3, which corresponds to raising seedlings,nutrition and heading period, respectively. If there is no input in acertain stage, the value inside is set to the preset value (For example,0). N is the feature dimension, and n is determined by the number offeatures of historical growth parameters. For example, if the historicalgrowth parameters include illumination intensity and illumination time,then n is 2. A certain element in the control parameter matrix is acertain parameter (illumination intensity or time) in a certain stage.

In some embodiments, the input of the growth feature layer furtherincludes the image features of the growth phenotype (growth potential)of at least one historical growth period. The image features of thegrowth morphology image of at least one historical growth period can beexpressed by the matrix t*1. Each matrix corresponds to each historicalgrowth period, t is the number of time points in the historical growthperiod, and a certain line in the matrix is the image feature at acertain time point, and the dimension of the image feature is 1.

In some embodiments, the growth feature layer input also includes thesoil detection results of at least one historical growth period. Thenutrient solution detection results of at least one historical growthperiod may be expressed by the matrix m*t, m and t are similar to theabove description, and the elements in the matrix are the nutrientsolution monitoring data of a certain stage and a certain time point.

In some embodiments, the growth characteristic layer input also includespreset illumination parameters of the target growth period. The presetillumination parameters of the target growth period can be expressed bythe vector of vector 1*h. A certain element of the vector is a presetillumination parameter, such as preset illumination intensity.

In some embodiments, the output of the growth characteristic layer isthe predicted growth quality of rice at the target growth period.

In some embodiments, the training samples of the illumination predictionmodel may include the sample historical growth parameters of the samplehistorical production stage, the sample growth morphology images of thesample historical production stage, the sample nutrient solutiondetection results of the sample historical production stage, and thesample preset illumination parameters, etc. The label may be the growthquality of the sample growth stage after the historical growth period,and the label may be obtained by manual labeling.

In some embodiments, the sample growth morphology image in the samplehistorical growth period is input into an image feature model in theillumination prediction model, the sample historical growth parameters,the sample historical growth morphology image. The sample historicalnutrient solution detection results, the sample preset illuminationparameters and the output results of the image feature model are inputinto a growth feature model in the illumination prediction model, and aloss function is constructed based on the output and labels of thegrowth feature model, and the parameters of the image feature model andthe growth feature model are iteratively updated simultaneously based onthe loss function until the preset conditions are met and the trainingis completed. After the training, the parameters of the image featuremodel in the illumination prediction model may also be determined.

The parameters of the image feature model may be obtained by theabove-mentioned training method, which is beneficial to solve theproblem that it is difficult to obtain labels when training the imagefeature model alone in some cases, and may also make the image featuremodel better obtain the rice image features that reflect at least onehistorical growth period.

In some embodiments, the parameters of the image feature layer in theillumination prediction model can be obtained by training the evaluationmodel.

The structure of the evaluation model includes image recognition layerand result evaluation layer. The model type of the image recognitionlayer may be CNN, which is the same as that of the image feature layerin the illumination prediction model. The model type of evaluation layermay be fully connected layer or DNN, etc. The input of the imagerecognition layer is the growth phenotype image of rice in a certainhistorical production stage, and the image features of the growthphenotype image are output. The input of the evaluation layer is theimage features output by the image recognition layer, and the output iswhether the rice is qualified in this historical production stage.

The evaluation model may be trained based on historical data. Thetraining sample includes the image of sample growth morphology in thehistorical growth period of the sample. The label is whether the ricegrowth in the sample growth morphology image is qualified or not. Labelsmay be generated by manual identification.

Compared with the illumination prediction model, the training samples ofthe evaluation model are easier to obtain. More importantly, the labelsof the training samples of the evaluation model are easier to judgemanually than those of the illumination prediction model. However, theimage feature layer needs a large number of training samples to ensurethat the extracted features are accurate enough. By transferring theparameters of the image recognition layer in the evaluation model to theillumination prediction model, the accuracy of model processing can beensured and the difficulty of sample acquisition can be reduced.

S4, the target illumination parameters of the target growth period aredetermined according to the at least one predicted growth qualitycorresponding to the one or more preset illumination parameters.

In some embodiments, the optimal predicted growth quality may bedetermined according to the ranking of at least one predicted growthquality, and the preset illumination parameters corresponding to theoptimal growth quality may be used as the target illuminationparameters.

The above-mentioned embodiments only describe the preferred mode of theinvention, and do not limit the scope of the invention. Withoutdeparting from the design spirit of the invention, all kinds ofmodifications and improvements made by ordinary technicians in the fieldto the technical scheme of the invention should fall within theprotection scope determined by the claims of the invention.

What is claimed is:
 1. A method for rice growth based on the regulationduring vegetative growth period of the rice, comprising soaking seeds ofthe rice, germination of the soaked seeds of the rice, cultivation ofthe germinated soaked seeds of the rice, managing and regulating of therice at a growth stage, and harvesting the rice, wherein the managingand regulating of the rice at the growth stage includes regulation ofdynamic light quality and photoperiod environment during the vegetativegrowth period of the rice; wherein the regulation of dynamic lightquality and photoperiod environment during the vegetative growth periodincludes: cultivating under the conditions of mixed light source withthe ratio of red light:blue light:white light of 0.8-1:0.8-1:1.0,photoperiod of 16-18 h and illumination intensity of 200-300 μmolm⁻²s⁻¹;wherein the red light has a wavelength of 660 nm, the blue light has awavelength of 450 nm, and the white light has a wavelength of 400-700nm.
 2. The method of rapid generation-adding growth of rice according toclaim 1, wherein the managing and regulating of the rice at the growthstage further comprises: adding Hoagland nutrient solution with 5%-10%of calcium nitrate during the vegetative growth period.
 3. The method ofrapid generation-adding growth of rice according to claim 1, wherein thesoaking seeds of the rice comprises cleaning the seeds of the rice andsoaking them for 12-24 h.
 4. The method of rapid generation-addinggrowth of rice according to claim 1, wherein the germination of thesoaked seeds of the rice comprises: culturing the seeds of the riceafter soaking in the dark at 22-25° C. for 36-48 h.
 5. The method ofrapid generation-adding growth of rice according to claim 1, wherein thecultivation of the germinated soaked seeds of the rice comprises:culturing the germinated soaked seeds of the rice under the conditionsof mixed light source with the ratio of red light:blue light of 2-5:1,illumination intensity of 100-150 μmolm⁻²s⁻¹ and photoperiod of 14-18 h.6. The method of rapid generation-adding growth of rice according toclaim 1, wherein during the cultivation of the germinated soaked seedsof the rice and the managing and regulating of the rice at the growthstage, the day/night temperature of rice breeding is (27-30° C.)/(23-25°C.) and the air relative humidity is 65-85%.
 7. The method of rapidgeneration-adding growth of rice according to claim 1, wherein theharvesting of the rice includes harvesting and threshing mature riceears, treating them for 5-7 days under the condition of air temperatureof 28-30° C., air humidity less than 40% and ventilation, reducing themoisture content of seeds to 6%-13%, and then storing the seeds at lowtemperature.
 8. The method of rapid generation-adding growth of riceaccording to claim 7, wherein the low temperature is 0-4° C.
 9. Themethod of rapid generation-adding growth of rice according to claim 1,wherein the managing and regulating of the rice at the growth stagefurther comprises: acquiring one or more historical growth parameters ofat least one historical growth period of the seeds of the rice before atarget growth period, wherein the target growth period is the vegetativegrowth period; acquiring one or more preset illumination parameters; foreach of the one or more preset illumination parameters, according to thehistorical growth parameters of the at least one historical growthperiod and the preset illumination parameter, determining a predictedgrowth quality of the seeds of the rice in the vegetative growth periodunder the action of the preset illumination parameter based on anillumination prediction model; and determining one or more targetillumination parameters of the vegetative growth period according to thepredicted growth quality corresponding to each of the one or more presetillumination parameters.
 10. The method of rapid generation-addinggrowth of rice according to claim 9, wherein the historical growthparameters at least include historical illumination parameters; and theone or more preset illumination parameters include preset illuminationtime and preset illumination intensity.